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Emergency Response to the Tesla Model 3 [video] (youtube.com)
32 points by CaliforniaKarl 6 days ago | hide | past | web | favorite | 49 comments

Interesting. Tesla seems like a lot more cumbersome vehicle to perform dash evolution/extrication due to the presence of the high voltage battery.

for example, in a traditional vehicle, a dashbeam blowout is performed using a higher speed ram. Without this, you have to make 3-4 more cuts to the vehicle


Tesla model access for the rocker channel is also inconsistent and a little scary. Rocker cuts made to the X for example seem to be permitted, however in the model S they might be lethal. I really wish they had more in the series on this.

disclosure: I was a volunteer firefighter for a few years after highschool.

Considering that Tesla's cars are significantly less likely to flip, significantly less likely to catch fire, slower to burn when they do catch fire, and the safest cars ever tested by the NHTSA ...is it fair to say that the added extraction complexity is somewhat of an acceptable trade-off?

>>> are significantly less likely to flip, significantly less likely to catch fire, slower to burn when they do catch fire, and the safest cars ever tested by the NHTSA

All of which means nothing if you are a firefighter trying extract someone from a crashed car. Tesla or no Tesla, it is still a car. It will be involved in accidents. It will crash. Someone will be trapped and someone will attempt to extract them.

There are certain scenarios that, although exceedingly rare, must still be contemplated. We cannot have a car from which firefighters cannot safely extract people. Even it only ever happens once in the next century, we aren't going to leave that person inside the car to die.

> we aren't going to leave that person inside the car to die.

Well... we already did. https://www.autoblog.com/2019/02/25/fatal-tesla-model-s-cras...

People at the scene tried to break the windows, but the fire got too hot and they were forced to leave the man behind and get smoked inside of the fire.

People are already dead because they were unable to be extracted from a damaged Tesla S. The only question now is how will Firefighters respond to the NEXT crash, and will they be prepared this time?

Also, Tesla probably should change the design of their cars to make for better emergency extractions, to minimize this risk. Obviously, doors and stuff will break and become unable to open during a crash situation. But when you have electronic handles that pop up and very confusing instructions for "emergency door" things in your manual (open the side compartment, look for a particularly colored wire, and pull on it? That's too complex, most people won't be able to do that while suffering from a concussion + fearing for the fire that's engulfing them).

Falcon Wing doors / Fancy handles are all fun and games until you consider the crash + burning situation. It really does make for a difficult extraction.

I would also look at the IIHS test results. Take the Model S for instance---it only gets an "acceptable" rating on the front driver side small overlap test, a test which many other cars are earning a "good" rating on.

Sure, Tesla's cars are generally very safe, but there is more than one way to measure safety, and Tesla doesn't always win.

>and the safest cars ever tested by the NHTSA

Stop spreading blatant falsehoods.


“A 5-star rating is the highest safety rating a vehicle can achieve,” the agency said in the statement, which did not name Tesla. “NHTSA does not distinguish safety performance beyond that rating, thus there is no ‘safest’ vehicle among those vehicles achieving 5-star ratings.”

>significantly less likely to catch fire, slower to burn when they do catch fire

Citation please. This directly contradicts the anecdotal experience of literally everyone I know who deals with crashed vehicles (10 < sample size < 20, ~66% tow truck drivers). Compared to other EVs Teslas definitely seem to be the most flammable. Everyone who handles crashed cars seems to regard a mangled Tesla as a hot potato unlike a Prius, Leaf or ICE car.

The NHTSA stuff and crash safety I believe, that's well documented by reputable sources (e.g the NHTSA). Nobody except Tesla and their fan-base seems to be saying EVs are less flammable on a per crash basis though and even then nobody says point blank that crashing a Tesla is less likely to result in fire than crashing something else.

Edit: I am specifically talking about the likelihood of fire per serious crash. Not average number of fires per vehicle or per mile.

"/r/teslamotors: Are Teslas historically more likely to catch fire? I did an Excel and the answer won't surprise you." [1] [2]

[1] https://i.redd.it/h7qse91ostt21.png

[2] https://www.reddit.com/r/teslamotors/comments/bg2rib/are_tes...

Disclaimer: Model S, X Owner

Who needs engineers, when we have choir teachers on Reddit.

What the engineers and scientists at the National Highway Traffic and Safety Administration have to say:

"Regarding the risk of electrochemical failure, [this] report concludes that the propensity and severity of fires and explosions from the accidental ignition of flammable electrolytic solvents used in Li-ion battery systems are anticipated to be somewhat comparable to or perhaps slightly less than those for gasoline or diesel vehicular fuels. The overall consequences for Li-ion batteries are expected to be less because of the much smaller amounts of flammable solvent released and burning in a catastrophic failure situation."

Like anything else, it's a risk discussion, and there is no simple answer. Tesla's are generally safe, as are gasoline vehicles, and there are risks and considerations that first responders need to train for, just like any vehicle chassis.

Source: https://www.nhtsa.gov/sites/nhtsa.dot.gov/files/documents/12...

Maybe the fact that rich, educated people drive Teslas, and poor, uneducated drivers don't accounts for it (my hypothesis is that rich, educated drivers have fewer accidents on average since they are less likely to DWI, etc)?

To control I would want to see what % of Tesla crashes catch fire compared to ICE crashes.

Driver status aside (no idea how to judge that), stats for regular vehicles rarely include only less than 5 years old, premium cars. A 15 year old unmaintained clunker is probably more likely to catch fire in case of an accident. I would imagine that considering models from the same years and same price range might paint a different picture.

What makes you think that rich people are less likely to drive drunk?

The problem with that analysis, as pointed out in the reddit comments https://www.reddit.com/r/teslamotors/comments/bg2rib/are_tes...

> This is misleading, the average vehicle on the road is much older than a tesla. You should represent the data showing in rate of fires per model year

If you read further down the thread you linked to, the cause of vehicle fires in older ICE vehicles is due to neglected maintenance (maintenance not required in an EV).

EVs have no ignitable fluids, nor hot surfaces to ignite those fluids. Ergo, their risk of spontaneous combustion during operating goes down drastically. I concede they may still catch fire after an accident severe enough to breech the battery; this is not preventable due to the energy storage requirements of a light vehicle, combustion-based or otherwise.

We don't have 15 year data on Tesla vehicles, period. There are theoretical arguments about how the batteries won't explode or corrode, but an apples-to-apples analysis would compare vehicles of similar maintenance and age. The citation the (unfortunately downvoted) parent was asking for was about the statistical claims.

The real story here is a choir teacher is not a proper source or a replacement for teams of Scientists and Engineers that do these crash analysis for a living.

The voting around this chain is really disappointing for a community that at least claims to be more well-versed in technical and math areas. Statistical claims that parrots Tesla's marketing is upvoted, a request for citation is heavily downvoted, and a flawed statistical presentation is upvoted while critiques are downvoted.

The downvotes are because the pessimists are asking for data that doesn't exist (due to how new most EVs are in general), and ignoring data that does exist (that EVs don't spontaneously combust as frequently as internal combustion vehicles).

No one is parroting Tesla's marketing (I'm unsure where they even market "our cars don't catch fire" explicitly), and the only way to accurately make a determination will be to wait until the average vehicle age of the EV fleet arrives at parity to the existing internal combustion fleet (as you mention in your own comment [1]).

[1] https://web.archive.org/web/20190711204039/https://news.ycom...

So in that case, the original claim [1] should never have been made. Why that is being upvoted so heavily, given that the claim is not justified by the numbers, is the real surprise here.

[1] https://news.ycombinator.com/item?id=20414075

Perception is reality and the numbers don't exist to make a concrete claim either way. This shouldn't be a surprise at all, regardless of forum. People will arrive at conclusions with the data available to them.

But saying "the risk is not yet quantifiable" isn't that exciting of a discussion topic.

You're comparing late model luxury cars to ALL cars? Do you see anything wrong with that?

One of those cells gets punctured and i assure you that there will be fire.

Can't cheat physics. Batteries include their own fuel, oxygen and ignition source. Once you mix them all together there WILL be fire.

I'm not sure what ram speed has to do at all with extrication. The biggest problem area I see with the model 3 is the fact that a large portion of the high voltage carriers are centerline on the vehicle. In our department using the center post for dash lift/roll allows us to work both front seats without obstructing patient egress via the side/door. In the Model 3 you don't have the option to roll from the center.

What's a rocker channel?

Rocker panel.

Edit: Why is this down voted? It it literally the same thing. The firemen may call it a channel (and the sheet-metal is roughly of a shape that people in the metal industry would refer to as a "channel") but the terms are interchangeable, it's the lower outboard edge of the passenger cabin.

It’s not a very informative comment.

The obvious next question is: what’s a rocker panel?

That's an easily answerable question.

Everyone here has an internet connection. Swapping an obscure term for an industry standard term should be enough to make search engines useful.

If I wanted to spoon feed people I'd go to Reddit.

A brief description of the component in question would be appreciated.

One of the benefits of describing what a rocker panel is in your own words, or even quoting and providing a reference, is that it encourages discussions here.

From what I've been reading this morning the rocker panel is the structural and component of the vehicle immediately under the side doors, and also includes the visible panel.

Is that a good enough approximation? If you're able to provide more information that'd be great!

I wonder if we'll see more standardization in electric vehicles so that fire departments don't need specific vehicle training to know what to cut and where.

Although we haven't seen that yet with hybrids (that also contain potentially hazardous batteries) that have been around longer.

I wonder this too.

Military jets have a "RESCUE" lever by the canopy to disarm the ejection seats. I wonder why cars don't have something standard and simple like that.

If every car model needs unique training on what secret cuts to make in what order, that's a fail.

Most US electric cars now have a cable marked with a yellow and red first responder cut point tag. You can see that briefly in the video. You cut the cable on both sides of the tag, so that the remaining ends can't touch, and the battery is isolated. There are where-to-cut guides.[1]

[1] https://www.ncdoi.com/OSFM/RPD/PT/Documents/Coursework/EV_Sa...

I think you also want to disable unfired airbags after the car has stopped crashing. There are cases where rescuers leaned in on passenger side, putting pressure on seat, and had the airbag deploy on them. I think there's other concerns that cutting door sills can cause deployments.

Oh and killing the engine would be good too.

I don't think I want to have a "kill power" switch on the side of my vehicle where a random up-to-no-good kid (or adult) can kill power to my car while I'm driving it.

Disclaimer: I ride a bike.

For what it's worth, there actually are kill switches on the sides of the ICE buses that service my university campus. Opening the little hatch and pushing the button disconnects power from the battery and kills the engine.

I imagine it's useful in situations where the engine has caught fire and you need to stop fuel flow ASAP. I've never heard of people abusing it, probably because everyone on board the bus including the driver could easily ID the wrongdoer. Of course, private personal vehicles are a different story.

Tesla vehicles disengage the high voltage contactors when an accident is detected. You still don't want to cut through parts that can't be de-energized (ie do not push through the floor pan into your energy storage system). There is also a "first responder cut loop" which does the same, similar to the mentioned "RESCUE" lever on an aircraft cockpit.

>Tesla vehicles disengage the high voltage contactors when an accident is detected.

Great! Is there a visual indication that has occurred (see for example F1: https://www.racecar-engineering.com/tech-explained/f1-2014-e...). If not,

>You still don't want to cut through parts that can't be de-energized (ie do not push through the floor pan into your energy storage system).

You're right! That's why these things are standardized and labeled (http://www.solotogrouptravel.com/wp-content/uploads/2014/01/...)

>There is also a "first responder cut loop" which does the same, similar to the mentioned "RESCUE" lever on an aircraft cockpit.

The point isn't the function it's the labeling. As noted in other discussions (https://jalopnik.com/tesla-model-3-teardown-by-engineering-f...) of the model 3...there are no externally visible markers of where to cut until you open or remove panels and the markings themselves are unclear. The front first responder loop requires a 12V battery be connected to the vehicle if the frunk won't open under vehicle power.

None of this is about whether or not such systems exist...all of this is about the design and indication necessary of those systems in emergency situations. All F1 cars have different manufacturers...but they all have the same iconography and processes for disarming potentially energized systems (e.g., put the car in neutral, put out a fire, check if car is electrically safe). That commonality means it is easy to train first responders AND for first responders to know what to/not to do in an emergency.

I'm willing to bet my Hurst spreaders will get the frunk open sans battery. If you're cutting the car, it's already totaled and limiting damage to the frunk would be the last concern on my mind.

You willing to apply them to something that you are trying to open specifically because you are concerned about the electrical state of the car?

Your spreaders will open it like a tin can...but did Tesla rev the location in real time during manufacturing?

Yeah, prying the frunk open and cutting the battery cables is the first thing they do in the video

I went back and rewatched it. I completely forgot they forced it. I first saw this a couple months ago when our TC used it for extrication refresher. I have to admit, even though it is staged and the car is completely intact, watching those guys is money. Super smooth execution. The way he handled the halligan solo to create the frunk gap was pleasing to watch.

In amateur and pro sportscar racing, all cars are required to have a prominent kill switch that cuts the main power from the electrical system, and this is just with 12V ignition and accessory systems.

It's always seemed like a great idea , and I expect that the only reason it isn't done in ordinary street cars is that the companies never liked reminding people of the potential of accidents (with some exception by Volvo & occasional others selling superior safety).

Typically there is a relay at the battery to cut high voltage to the rest of the vehicle. Also, some components have requirements to discharge internal capacitance (and hence the bus) in a short time. A crash should trigger all this, but I suppose from a safety POV you can never be completely certain.

I was thinking internal fuses for each cell, then you've nothing worse than a couple of volts.

Imagine if first responders had to watch a 20 minute video for each of the several hundred models of cars that are on the roads. Doesn't seem like a scalable approach.

We don't. It's a cool video for a training night but really it's a pretty standard dash roll. Electric cars present a very real danger but so do ICE. High pressure fuel lines with pumps that don't shut down. Diesel engines which "runaway" with air intake leaks.

Every call is a special situation where you start with a baseline tactic and evolve the approach as needed. 20 minutes is overkill but the whole time we were watching it here we were discussing extrication in general. "Would you do this or that? What would you look for here? Did you see their step cribbing placement?" The Tesla responder guide is awesome and available online and is all you "need" to know where and what to cut. The video is more a conversation starter.

I know it's necessary for safety, but it always makes me sad to see cars destroyed for crash tests and fire safety testing.

If you look closely, it appears the Model 3 they used in the dash displacement later on in the video had some damage on the sides — it may have already been salvaged or totaled.

At least they made good use of a basically dead vehicle assuming that's true.

Use the sadness as motivation to start a VR project which enables fire fighters to simulate safety training? :)

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